The present invention relates to a yarn withdrawal apparatus for use with a yarn processing apparatus of the type which continuously processes and advances a yarn along a predetermined path of travel, and wherein the withdrawal apparatus is adapted to continuously withdraw the advancing yarn from the path of travel when the operation of the processing machine is interrupted, to facilitate yarn thread-up and the like.
The above copending applications disclose apparatus of the described type and which are adapted to apply a relatively high yarn tension to the advancing yarn, at speeds of up to 4,000 meters per minute and above. Also, as is indicated in the above copending applications, it is not a significant problem to catch a delivered yarn end with a suction gun or an air current, when the yarn is advancing directly from the spinneret. However, the prior applications also recognize that a relatively high tension is necessary to prevent laps from forming on the yarn delivery system positioned downstream of the spinneret, and the required high tension may be achieved when the air current is assisted by a mechanical yarn advancing system.
It is an object of the present invention to provide an improved yarn withdrawal apparatus of the described type, and which provides for a reliable catching of the delivered yarn end in the air current.
It is also an object of the present invention to provide an improved yarn withdrawal apparatus which is simple to operate and which permits the captured yarn to be readily looped about the yarn delivery system of the yarn processing machine, without risk of lap formation.